What are the answers to existence? More than two thousand years ago, a few individuals in a small number of Greek city-states that included Classical Athens dedicated their lives to the pursuit of understanding and knowledge and, in doing so, changed the way we think about the world and ourselves today. It was this effort that captivated Thales, Axanimander and Heraclitus – and those who built upon what they had created – thinkers such as Socrates, Plato, Aristotle, Diogenes, Epicurus and Pyrrho. Together, they invented the discipline of philosophy, the practice of contemplating knowledge, reality, purpose and being. What we have inherited from them has shaped our present-day concepts of evil, virtue, duty, justice, and the meaning of life itself.